Machining is the largest single application of lasers to materials processing. Laser cutting of metallic materials is finding increasing use in industrial applications but is generally limited to thin sections (less than 5 mm). Thicker- section metal cutting with lasers suffers from several drawbacks that include lack of heat penetration, large kerf width, poor cut quality, and problems associated with material removal and heat transfer. A thermochemical approach involving the application of two adjacent, high-power laser beams in Gaussian energy configuration and various organic assist gases (C2 H2, C3 H8, and C7 H18) along with oxygen will be investigated with a view to extending the performance limitations of laser cutting without deteriorating the cut quality. Heat transfer, fluid flow, and chemical reaction phenomena will be considered in developing theoretical models that will closely predict the experimental results. The mathematical approach combined with the proposed experiments will provide valuable insight into the nature of physical phenomena, facilitating efficient laser cutting of materials much thicker and at speeds faster than those that are possible currently. The proposed research will be particularly relevant to high- technology manufacturing industries that use laser machining.
